Circadian cycles, menstrual cycles, and seasonal cycles guarantee that the biology of the human body isn’t constant throughout the day, the month, or the year. Building on this fact, chronotherapy is the practice of coordinating the taking of medical drugs and treatments with our biological rhythms. In one study it was found that scheduling breast cancer surgery at different points in a woman’s menstrual cycle changed the likelihood of tumor reoccurrence after 5 years from 76% to 63%. Other diseases, such as asthma and arthritis, follow daily patterns, and timing medication doses can maximize blood levels of medications during the worst daily phases of them. (A time to Heal: Chronotherapy Tunes into Body’s Rhythms) And taking chemotherapy at the right point during the day has been found to boost its cancer treatment effectiveness while minimizing side effects. (Circadian rhythms boost cancer therapies)
Not respecting our body’s natural rhythms can create a host of problems. Researchers have found that people who repeatedly disrupt their normal circadian cycle over years could be suffering shrinkage of their temporal lobes, and this in turn seems to affect short term objective memory and simple abstract cognition. Previous work has suggested that such disruptions might also affect heart disease and breast cancer risks. One reason why this could be is that the pineal gland secretes melatonin at night, and disruption of this system has been implicated in cancers. (Jetlag ‘shrinks the brain, Artificial lighting in the industrialized world: circadian disruption and breast cancer by Richard G. Stevens, and (Shortness of Dark by Allen Bellows) At night the body stays awake by activating the stress response, and this in turn weakens the immune system. The scheduling of surgery from morning to afternoon can affect the rate of adverse health events due to anesthesia, and part of this could be due to people being at different points of their cycles. (Time of Surgery Influences Rate of Adverse Health Effects Due to Anesthesia) There is even the concern that exposing infants to constant light prevents infants from developing normal circadian rhythms to begin with. (Artificial Light and the Biological Clock)
Michael Smolensky, et al., even advocate that people should construct their own personal “chronorecord,” which is a recording of all their cycles. In this way a person can synchronize their internal clock with their health care and other various activities. (The Body Clock Guide to Better Health: How to Use Your Body’s Natural Clock to Fight Illness and Achieve Maximum Health (Paperback) by Michael Smolensky)
